Chasing Mr Channing
by varjaks
Summary: John is set to leave for his honeymoon with Mary when he and Molly are called in to help Lestrade catch a serial killer. Fortunately for the groom, Sherlock Holmes, St. Bart's pathologist and his best man, reluctantly steps in to take his place. [oneshot Swaplock; post-TRF; birthday gift to the talented Adi Who Is Also Mou]


A/N 1: Been a while since I've written a proper Swaplock fic, hasn't it? Going out of hibernation for the lovely Adi, who I hope enjoys this little birthday present. There's a bit of romance here if you look at it carefully.

A/N 2: This is not a continuation of my previous Swaplock fic _To Shape to the Comfort of Us._ However, it does operate on the same headcanon. It's not necessary, but it might be helpful for new readers to refer to that before delving into this. As I said before, my headcanon for Swaplock is more than a smidge different from the others.

Disclaimer: I still don't own any of the characters except for the poor Miss Penelope Hunt and Mr. Alan Channing.

* * *

"You're joking." John narrows his eyes at the apologetic look on Lestrade's face. He shrugs off his blazer and starts tugging his tie with more violence than necessary. "It had to be today. _Now._ It had to happen _now._"

"I'm sure the victim was thinking along similar lines before her head was hacked off," Molly mutters distractedly while studying the crime scene photos in Lestrade's mobile. "Of course, I doubt Miss Penelope Hunt knew we'd be called in during your wedding reception."

"Listen, I know the timing is terrible. Believe me, if I had any say in the matter, there wouldn't be a single victim." This development in Scotland Yard's newest high-profile case brings out the frown lines and shadows on the detective inspector's face. John curses himself when his resolve starts to crumble. "But this is the fifth girl the bastard got his hands on. Maybe this time he's slipped and there's something you two can find to help us stop him before he starts again."

"Of course." Molly hands back Lestrade's mobile and trades her heels for the foldable flats she keeps in her purse. "John, Mary, sorry for rushing off like this but I'm sure you two understand. Enjoy the rest of the evening and I'll see you both after the honeymoon."

Mary, still dressed in her wedding gown, takes it all in stride and accepts a hug from Molly. "As soon as we're back, you and I are having another girls night. I want to hear all about how you caught this one."

John would have smiled at the proof of the easy friendship between the two women, but as it stands, he's too stunned to do anything but stare. "What do you—are you mad? I can't leave when you're here running after this serial killer alone."

Molly considers bringing up the last three years she spent dismantling Moriarty's web but thinks better of it. "You and Mary are leaving tonight, and that's final." She can't stifle a frustrated sigh when John, crossing his arms across his chest, looks at her unconvinced. "I'll be working with Greg, remember?"

"And when he's not there?"

Molly turns to the only person in the room who has yet to speak. "Sherlock?"

The pathologist is surprised to find everyone looking at him expectantly. "You can't be serious. You're all suggesting I start running after criminals with Molly?"

"Just until I'm back. Think of it as an extension of your duties as my best man," John says, giving the taller man a pat on the shoulder. "Here's a secret: Only about 20% of the job involves running. The rest of the time is spent waiting for Molly to put everything together."

"If you two are done talking about me like I'm not here, there's a crime scene waiting," Molly calls over her shoulder as she follows Lestrade out the door.

"After everything that's happened…" Sherlock recognizes the haunted look that passes over John's face; he's seen it too many times after the Fall and works only too well on his still guilt-ridden conscience. "There's no one else I trust more to have her back while I'm gone."

A beat passes before Sherlock's on his feet, albeit still reluctant. He doesn't miss the pleased looks John and Mary give him."And you'll be back in two weeks?"

"Yes."

Sherlock nods to the new Dr. and Mrs. John Watson, and hurries after Molly.

.

.

"Didn't John say something about 20% running?"

They're tearing down the streets of London, ducking around bins and people stumbling out of pubs, and Sherlock doesn't know where he finds the breath to speak. The heavy footfalls of Alan Channing sound closer but Molly pulls him forward and makes a sharp left turn. His heart is still pounding even after Alan, the serial killer they'd been following (how the roles were reversed is still hazy), rushes past the small alley.

"Are you alright?" Molly squeezes his hand and doesn't let go until he nods. She fishes out her mobile from a coat pocket and calls Lestrade. Past the sound of blood rushing in his ears, Sherlock can make out bits of the conversation. "Yes, Alan Channing—no, not the neighbor—killed his accomplice tonight—"

He leans against the brick wall and contemplates what _bloody liar_ John Watson is, when he notices the sly look Molly gives him. "He couldn't have gotten far from here. Sherlock's aim with a screwdriver is surprisingly good."

Lestrade must have yelled the next part because his voice echoes in the small space. "No, it's nothing fatal. Just a stab to the leg, and still far from the femoral artery."

Sherlock briefly wonders what Mycroft will say when one of his government cronies hands him the video from tonight. He sighs and realizes that he'll probably find out in few hours.

"I thought you said that you're alright?"

It takes Sherlock a moment to realize that Molly is talking to him, her mobile tucked back inside a pocket. She looks at him curiously, her eyes studying closely for injuries he may be hiding from her.

"I am." Molly raises a brow at him, and he can feel a flush starting at his neck. Sherlock flattens a hand over his scarf gratefully. "Alright, that is."

She still looks unconvinced but nonetheless drops the subject. "Lestrade should have Alan Channing in Scotland Yard before midnight. So, how do you feel about coffee?"

Sherlock blinks. "Coffee?"

"Lestrade will bring Mr. Channing to the A&E before the interrogation room. It's standard procedure but one that usually takes more than an hour to finish," Molly explains as casually as she would the weather. He follows her out of the alley and back to more familiar streets, where they quickly blend in with the crowds of people going about their usual business, completely unaware of the danger Sherlock and Molly just escaped from.

"Considering the timing—summer and a Friday evening—it will take them even longer than usual to find an available physician in St. Bart's," she continues, guiding them down a row of shops. "We might as well get coffee while waiting. This is probably going to be a very long night."

Despite her words, Molly is grinning up at him. Her cheeks are flushed and Sherlock assumes that, like him, she must still be running on adrenaline. It's no surprise that he soon finds himself smiling right back.

"There's a Costa a block away from here," he offers.

She nods, her eyes catching the light from the window displays, and gestures him forward. "Please lead the way."

.

.

_The case is almost closed. We're just waiting for Lestrade to interrogate Channing. - SH_

_Good. Did he give you any trouble? - JW_

_I took care of it with a screwdriver. - SH_

_A screwdriver? - JW_

_Turns out playing darts with you in the pub isn't a complete waste of time. - SH_

_What are you two doing now? - JW_

_Getting coffee. Aren't you supposed to be enjoying your honeymoon with your wife? - SH_

_Don't change the subject and Mary also wants to know. What do you mean coffee? - JW_

_It's rude for the best man not to reply to the groom. - JW_

_Sherlock! _

_._

_._

"Shouldn't you answer that?" Molly points to his overturned mobile, which has been buzzing from the continuous stream of texts. "They might need you for an emergency in Bart's."

Sherlock scrolls through his messages, leaves them unanswered, and slips his mobile into a pocket. "It's nothing, just Mycroft." Again, Molly looks unconvinced but lets it slide, shifting her attention to preparing her coffee. She slides two packets of sugar across the table, and he stills for second, his eyes fixed on the small white rectangles next to his fingers.

Sherlock eventually reaches for the sugar and thanks her before adding them to his drink. "So, any updates from Lestrade?"

"Not yet. Looks like we'll be waiting for a while." Molly sips her coffee, the edge of the mug hiding the upward curve of her lips.


End file.
